What absorbs at 1123 cm⁻¹ in an FTIR spectrum?
A band near 1123 cm⁻¹ can point to several functional groups. Below are the most likely assignments, ranked by how much published evidence supports each — every one traceable to literature (DOI) and cross-validated against our 130,000+ reference spectra and knowledge graph.
Backed by 7 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Alkyl C-H | 2 | 2 | 1.0 |
| S eq o | 1 | 1 | 1.0 |
| Silicon (Si) | 1 | 1 | 1.0 |
| Carbonyl (C=O) | 1 | 1 | 1.0 |
| Sulfonate | 1 | 1 | 1.0 |
| Boron nitrogen | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Boron nitrogen confidence 1.0
“cm-1 The characteristic peak of 1123 corresponds to vibration modes of the B-N+, Q = N+ and N = Q = N (Q and B represent the quinoid and benzoid units, respectively) due to protonation of PANI.”
Jin 等 - 2018 - Polymer anode used in hydrometallurgy Anodic beha DOI: 10.1016/j.hydromet.2018.01.020 -
Sulfonate confidence 1.0
“The S-O symCySO 2-S-Cy (1121 was found for keratin hydrolysates at 1121.9-1123.3 The cm-1 metric stretch band attributed to Cy-S-SO3 (Bunte salt) at 1015.8-1021.1 cm-1 and S-O S-O symmetric stretch band attributed to Cy-S-SO (Bunte salt) at”
Gaidau 等 - 2021 - Wool Keratin Hydrolysates for Bioactive Additives DOI: 10.3390/ma14164696 -
Carbonyl (C=O) confidence 1.0
“LLM confirmed rule peak-group candidate”
In Vitro MCF-7 Cells Apoptosis Analysis of Carboplatin Loaded Silk Fibroin Particles DOI: 10.3390/molecules25051110 -
Alkyl C-H confidence 1.0
“LLM confirmed rule peak-group candidate”
He 等 - 2020 - Flexible fabric gas sensors based on PANIWO(3)p-n DOI: 10.1007/s40843-020-1364-4 -
Alkyl C-H confidence 1.0
“The bands at 1123 and 1141 were attributed to the -CH twisting vibrations of transand 2”
Cotton functionalized with polyethylene glycol and graphene oxide for dual thermoregulating and UV-protection applications DOI: 10.1038/s41598-023-31415-z -
Silicon (Si) confidence 1.0
“Other absorption bands are particularly assigned as follows: 1123 and 1037 cm-1 (ν absorption bands are particularly assigned as follows: 1123 and 1037 asSi-O-Si cm-1 (νasSi-O-Si from Q3), 784 and 676 cm-1 (νsSi-O-Si), 613 cm-1 (νL(OH-)), 5”
Phase Composition of Silica Fume—Portland Cement Systems Formed under Hydrothermal Curing Evaluated by FTIR, XRD, and TGA DOI: 10.3390/ma14112786 -
S eq o confidence 1.0
“cm-1 licensed C-H tion of the amide group peak, 1180 is the on cm-1 Published deformation vibration (in-plane) of benzene ring, 1123 is S]O the asymmetric absorption peak of bond of sulfonic acid is cm-1 article”
Synthesis, characterization and properties of a novel environmentally friendly ternary hydrophilic copolymer DOI: 10.1039/d3ra00811h
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